Position of a point on a turning wheel..

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SUMMARY

The discussion focuses on calculating the position of a point on a wheel with a diameter of 60 cm, which rotates with a constant angular acceleration of 4 rad/s². At t=2 seconds, the angular speed is determined to be 8 rad/s, while the linear velocity of point P is 2.4 m/s and the tangential acceleration is 0.5 m/s². The user struggles with finding the angular position of point P, initially calculating it as 98.36 degrees above the horizontal using the formula θ = θ₀ + ωᵢ*t + 1/2*α*t².

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imatreyu
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Homework Statement


A wheel 60 cm in diameter rotates with a constant angular acceleration of 4 rad/s^2. The wheel starts at rest at t=0, and a chalk line drawn to a point P on the rim of the hweel makes an angle of 57.3 ith the horizontal at this time. At t 2s, find (a) the angular speed of the wheel, (b) the linear velocity and tangential acceleration of P, and (c) the position of P.

a. 8 rad/s
b. 2.4 m/s, 1/2 m/S^2
c. ? :(
I did parts a and b, but do not understand how to do part c.


Homework Equations



wf^2 = wi^2 + 2 [tex]\alpha[/tex]theta

The Attempt at a Solution



wf^2 = wi^2 + 2 [tex]\alpha[/tex]theta
(8 rad/s)^2 = 0 + 2(4 rad/s^2)theta
theta = 8 radians
Convert to degrees--> 458 degrees
458 - 360= 98.36 degrees above the horizontal


Could someone please tell me what I'm doing wrong? I'm pretty sure I'm doing something wrong. Haha. . .

Thank you in advance!
 
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Use the formula

θ = θο + ωi*t + 1/2*α*t^2.
 

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